亚胺基二乙酸树脂对镧(Ⅲ)的吸附及其机制  

Adsorption Behavior and Mechanism of Diglycolamidic Acid Resin for Lanthanum(Ⅲ)

作　　者：沈秋仙[1] 莫建军[1] 熊春华[2] 

机构地区：[1]丽水师范专科学校化学系,浙江丽水323000 [2]杭州商学院食品生物与环境工程学院,浙江杭州310035

出　　处：《中国稀土学报》2003年第4期421-424,共4页Journal of the Chinese Society of Rare Earths

基　　金：浙江省高校中青年学科带头人基金;浙江省自然科学基金项目资助(200072)

摘　　要：研究了亚胺基二乙酸树脂(DAAR)对镧离子的吸附行为及机制,pH=5.73的HAc NaAc体系为最佳吸附条件。静态饱和吸附容量为188mg·g-1·R;表观吸附速率常数k298=2.00×10-5s-1,表观吸附活化能Ea=9.57kJ·mol-1;等温吸附服从Freundlich经验式;吸附热力学函数ΔH=10.2kJ·mol-1;ΔS=45.0J·mol-1·K-1;ΔG298=-3.17kJ·mol-1;用0.5mol·L-1HCl作解吸剂,解吸率接近100%;树脂功能基与镧离子的配位摩尔比为3∶1;化学分析及红外光谱表明树脂功能基上的O与La3+发生配位键合。The adsorption behavior and mechanism of diglycolamidic acid resin(DAAR) for lan thanum were investigated. The optimal adsorption condition of DAAR for La(Ⅲ)is pH 5.73 in HAc-NaAc medium. The statically saturated adsorption capacity is 188 m g·g-1·resin at 298 K. The apparent adsorption rate constant is k  298=2.11×10-5 s-1. The apparent adsorption activation energy of D AAR for La(Ⅲ) is 9.57 kJ·mol-1. The adsorption behavior of DAAR for La( Ⅲ) obeys the Freundlich isotherm. The adsorption parameters of thermodynamics a re ΔH=10.2 kJ·mol-1, ΔS=45.0 J·mol-1·K-1, ΔG 298=-3.17 kJ·mol-1 respectively. HCl can be used as an eluant . The elution percentage is near to 100% when the concentration of HCl reaches 0 .5 mol·L-1. Coordination molar ratio of the functional group of DAAR to L a(Ⅲ) is 3∶1. Chemical method and IR spectrometry show that the oxygen atom of the functional group of DAAR coordinated with La(Ⅲ) to form coordination bond.

关 键 词：无机化学 吸附 机理 亚胺基二乙酸树脂 镧(Ⅲ) 稀土 

分 类 号：O614.33[理学—无机化学]